That was the pre-show to the old 'Here come the Muppets" show at Disney MGM studios. the show itself was a 15 min performance with walk-around Muppets (Kermit, PIggy, Fozzie, Gonzo, Bean, and the EM band). But the presehow was this hilarious bit featuring Rowlf and Sam with Rowlf basically singing various songs (Lydia the Tattooed Lady, etc) and Sam interrupting and interjecting.

Anyway, if you look closely you can see Rowlf wearing a watch which he used to keep track of how much time was left before the show.